Amateur radio science to draw students into astronomy

March 22nd, 2018, Published in Articles: EngineerIT

Fig 1: Alex Artieda, ZS6EME, at his home in Pretoria.

There appears to be a misconception amongst many young people that engineering is not cool. This may be because engineers are not stepping up to share the great things they do. The new developments in electronics and communication we all enjoy just don’t happen by themselves. They require the skills of engineers, scientists, and inventors. There is a continuous debate about how to encourage more school-leavers to take up studies in one of the many branches of engineering. The simple answer is to make engineering and engineering studies cool!

Alex Artieda (ZS6EME), an amateur radio enthusiast involved in amateur radio astronomy (whose wife is the Swiss Ambassador in South Africa, on a four year assignment) recently visited the Square Kilometre Array (SKA) in the Karoo. He said that after his visit he understands how big the demand for South African scientists will be within the next years and how essential it is get more undergraduate students involved in astronomy science.

However, it is not easy to attract young university students into a career such as radio astronomy, as socio-economic pressures often force future professionals to favour more conventional careers where economic success is, theoretically, faster.

An adequate system to create interest among young university students can generate greater interest in science careers that, in the medium term, can boost and be the source of future South African scientists in projects such as the SKA.

Artieda is an engineer by profession and an enthusiastic radio amateur which gives him opportunities to experiment. His main passion is to communicate by bouncing signals off the moon, commonly known as earth-moon-earth (EME). This aspect of amateur radio offers many engineering challenges such as the development of highly sensitive receivers to decode weak signals bouncing off the moon and precision mechanics under electronic control to position a dish antenna or a stack of multi element beam antennas to accurately follow the moon as it orbits around the earth.

He said his EME activities in South Africa had amazed many people from official and private institutions dedicated to science and more specifically, radio astronomy. “When they visited my home and were able to hear their voices bounced off the moon, they expressed the view that this ‘amateur stuff’ could help develop future generations of South African scientists. Their comments gave me the inspiration to create a network of radio amateur radio telescopes to promote science amongst young undergraduate students.”

And so the idea for the South African University Radio Astronomy Network (SAURAN) was borne. The central idea of the SAURAN will be to install 20 radio telescopes at South African universities, initially with dishes and radio equipment to do EME communication on 1296 MHz, and later using the equipment for other radio astronomy projects.

Each station will be equipped with a 4,5 m parabolic dish antenna with an auto tracking system, the latest solid-state power amplifier (SSPA) and a HF/VHF/UHF transceiver. The transceiver will also be used for HF communication to develop radio skills of students.

Artieda recently held discussions with the South African Radio League (SARL) and AMSAT SA and both organisations agreed to support the project and assist with setting up radio clubs at universities where the SAURAN will be installed. The two organisations will facilitate students in becoming licensed radio amateurs, which is a regulated requirement to operate on frequencies in the amateur radio spectrum. He envisions that the SAURAN facilities will be open to all radio amateurs who do not have their own facilities so they too can become involved in EME and astronomy projects. They will also be encouraged to take high school groups to visit SAURAN facilities for learners to experience radio astronomy and amateur radio first hand.

The cost of the SAURAN project is estimated at R6,5-million and will be funded by the private sector. Phase one, the proof of concept phase, is progressing well with the funds for the first two stations being made available by private donors. Artieda says that after the pilot stage, he hopes to involve institutions like SKA South Africa, the National Research Foundation and the Department of Science and Technology.

The SAURAN will be administered by a committee with members representing the donors, the SARL, AMSAT SA and participating universities. “My time in South Africa is soon coming to end, but I want to leave my legacy in a social outreach project. If SAURAN becomes implemented it will be the first time in the history of humanity that an educational radio telescope network of such magnitude is implemented by any country in the world,” said Artieda.

History of EME communication

The use of the moon as a passive communications satellite was proposed in 1940 by W.J. Bray of the British General Post Office. He calculated that with the available microwave transmission power and low noise receivers available at the time, it would be possible to beam microwave signals from earth and reflect them off the moon. At least one voice channel would be possible.

Around October 1943 an experimental EME unit was built by Telefunken on the shores of the Baltic Sea. In January 1944 radar signals were inadvertently beamed towards the rising moon while some radar measurements were being conducted. Suddenly a strange series of pulses just 2,5 seconds after the transmission were observed. After a short time this effect disappeared as the moon moved out of the antenna beam. This moon echo effect was again tested during the next day at moonrise with positive results.

Serious development of EME techniques too place by the United States military in the years after World War II, with the first successful reception of echoes off the moon being carried out at Fort Monmouth, New Jersey on 10 January 1946 by John H. DeWitt as part of Project Diana. The Communication Moon Relay project that followed led to more practical uses, including a teletype link between the naval base at Pearl Harbour, Hawaii and United States navy headquarters in Washington, DC. In the days before communications satellites, a link free of the vagaries of ionospheric propagation was revolutionary.

The first amateur work at receiving one’s own echoes was accomplished back in 1953 on 144 MHz by two US radio amateurs. The first two-way contact on 1296 MHz, the frequency proposed for the SAURAN network, was made in the USA on 21 July 1960 by John Kutzet W1BU and Douglas Dowsa W6HB.

Contact Alex Artieda, SAURAN, info@linkrf.ch